David Thompson <dthomps...@worcester.edu> skribis:
> Andy Wingo <wi...@pobox.com> writes:
>
>> Two patches attached.
>>
>> Unfortunately to use this you need to expand out %base-services to add
>> upower to the udev-service form. Also you need the upower-service,
>> obviously, and upower needs to be added to the dbus-service form as
>> well.
>
> This isn't the first time I've seen people expanding out %base-services,
> and I was also planning to do so for my OS config. I wonder if we
> should create a 'make-base-services' procedure that accomodates the
> common tweaks to the %base-services list: the MOTD, the list of packages
> for dbus-service, etc.
In commit 4c9050c, I documented a trick to handle the situation where we
want to customize ‘nscd-service’ as an example:
As an example, the declaration below configures the NSS to use the
‘nss-mdns’ back-end (http://0pointer.de/lennart/projects/nss-mdns/),
which supports host name lookups over multicast DNS (mDNS) for host
names ending in ‘.local’:
[...]
Note that, in this case, in addition to setting the
‘name-service-switch’ of the ‘operating-system’ declaration,
‘nscd-service’ must be told where to find the ‘nss-mdns’ shared library
(*note ‘nscd-service’: Base Services.). Since the ‘nscd’ service is
part of %BASE-SERVICES, you may want to customize it by adding this
snippet in the operating system configuration file:
(use-modules (guix) (gnu))
(define %my-base-services
;; Replace the default nscd service with one that knows
;; about nss-mdns.
(map (lambda (mservice)
;; "Bind" the MSERVICE monadic value to inspect it.
(mlet %store-monad ((service mservice))
(if (member 'nscd (service-provision service))
(nscd-service (nscd-configuration)
#:name-services (list nss-mdns))
mservice)))
%base-services))
… and then refer to %MY-BASE-SERVICES instead of %BASE-SERVICES in the
‘operating-system’ declaration.
Not ideal, but that’s what we can do for now.
Ludo’.
